In the manufacturing of integrated circuits, wafers are involved, and are used for forming integrated circuits or for bonding dies thereon. The wafers are often too thin to endure the force applied in the manufacturing processes such as grinding. Accordingly, during the manufacturing processes, carriers are used to mechanically support the wafers in order to prevent breakage. At certain manufacturing stage, the carriers need to be de-bonded from the wafers. After the de-bonding of the carriers, there may be some remaining processes (such as grinding) that need to be performed on the wafers. Without the support of the carriers, however, the wafers may subject to warpage, and hence the subsequent process steps such as grinding may experience difficulty.